This is a WooCommerce plugin that implements facebook share and like button on the product page with flexible options. After you activated the plugin, the default option is 'Enabled' for all the existing products.
You can use shortcode '[fbsharelike]' or function call 'fbsharelike()' to output the button.

Under WooCommerce sidebar panel, there will be a new child menu link called 'FBShareLike Settings' section.